Study On Detection Method Of Voltage Fluctuation In Wind Power System

Energy crisis and environmental pressure directly affect people’s life, in order to solve the problem,new energy power generation is developing in recent years, such as wind power, photovoltaic power and geothermal powe. In western region of Inner Mongolia a unique advantage exists in developing wind generation and in recent 5 years in the west of Inner Mongolia area new grid connected power generation of wind power system up to more than 20. Output power and output voltage of wind power will change with the wind outside, so grid connection of large capacity wind power will produce certain influence to the safe and stable operation of the main power grid. In order to reduce the impact of wind power grid connected to the main power grid, the relevant fields are studying the method of voltage fluctuation detection for wind power system.Firstly, the impact of large scale wind power integration is described to lead to the necessity of wind power system voltage fluctuation detection. These methods involve peak voltage detection method, voltage effective value detection method, Fourier transform method, wavelet transform method and Hilbert-huang transform method. The characteristics of these methods are described and initially decided to apply Hilbert Huang transform to detect voltage fluctuation in wind power system.Then function simulation method, image method and waveform matching method are all analysed and through this local data of the original signal data continuation is summed up. Improved waveform matching method for endpoint data processing is decided to solve the problem of end effect, and the main idea is sampling period of time during different period waveform characteristics values of extension, the extension extension of the data closer to the actual situation.Finally, through the simulation analysis method, the feasibility of the improved method is verified. In West Inner Mongolia a wind power system voltage fluctuation situation is taken as an example to verify the practicability of the proposed method for validation studies and the sensitivity of amplitude variation and frequency variation curve is also analysed.